55 lines
1.3 KiB
Java
55 lines
1.3 KiB
Java
package it.cavallium.dbengine.lucene.searcher;
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import java.util.Iterator;
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import java.util.List;
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import java.util.function.Supplier;
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import java.util.stream.IntStream;
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import org.apache.lucene.search.IndexSearcher;
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import org.apache.lucene.search.ScoreDoc;
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public class LuceneMultiGenerator implements Supplier<ScoreDoc> {
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private final Iterator<Supplier<ScoreDoc>> generators;
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private Supplier<ScoreDoc> luceneGenerator;
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public LuceneMultiGenerator(List<IndexSearcher> shards, LocalQueryParams localQueryParams) {
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this.generators = IntStream
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.range(0, shards.size())
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.mapToObj(shardIndex -> {
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IndexSearcher shard = shards.get(shardIndex);
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return (Supplier<ScoreDoc>) new LuceneGenerator(shard,
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localQueryParams,
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shardIndex
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);
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})
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.iterator();
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tryAdvanceGenerator();
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}
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private void tryAdvanceGenerator() {
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if (generators.hasNext()) {
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luceneGenerator = generators.next();
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} else {
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luceneGenerator = null;
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}
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}
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@Override
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public ScoreDoc get() {
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if (luceneGenerator == null) {
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return null;
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}
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ScoreDoc item;
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do {
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item = luceneGenerator.get();
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if (item == null) {
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tryAdvanceGenerator();
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if (luceneGenerator == null) {
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return null;
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}
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}
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} while (item == null);
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return item;
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}
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}
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